In the state of the art, to remove the cork from a bottle the main steps are as follows: first the metallic or plastic protective cap (if any) which covers the cork must be removed; a self-threading screw is then made to penetrate into the cork until the thread has obtained a sufficient grip on the cork; the cork is then removed from the bottle, with a prevalently axial movement, with the help of one or more levers associated with one or more handles.
There are many corkscrews on the market which allow to carry out the above steps either manually or semi-automatically.
The most commonly used corkscrews are those operated manually; among them there is PCT N.sup.o WO-A-92/04273, of which the present Applicant is the Proprietor. This document discloses a corkscrew provided with a mechanism which allows to cut the protective cap when the screw is screwed into the cork, and then remove the part of the cap which has been cut together with the cork itself. This mechanism comprises a plurality of cutter wheels which are made to adhere to the cap by means of a system of levers activated by a sleeve which is made to slide axially with respect to the body of the corkscrew.
Even though it has solved a series of problems, this corkscrew still has the same disadvantages as all other manual corkscrews known to the art, that is, that all the operations have to be carried out by hand, with a considerable waste of time and energy on the part of the users, especially if they are restaurateurs or bartenders, or manage bars, pubs, inns or similar public premises, where such opening operations are frequently required.
There is also, in the state of the art, a device to remove corks wherein the screw, used to screw into the cork, is commanded by an electric motor. In this device the screw is laid on the upper part of the cork, the motor is fed electrically, so that the screw can turn and penetrate inside the cork, after which the motor is stopped. The device is then distanced from the bottle, until the cork has been removed. In this device, as the screw is not controlled in its travel, it normally penetrates the cork and completely perforates it, exiting through the inner end, with the disadvantage that it very often makes little pieces of cork fall inside the bottle and therefore into the content thereof, wine or other liquid whatever it may be.
Obviously, this is unacceptable, especially when the content is a valuable wine which must be served and drunk without any impurities.
U.S. Pat. No. 5,372,054 discloses an apparatus for automatically extract a cork from a bottle, wherein a corkscrew is associated to a reversible electric motor which, with a clockwise rotation, completely penetrates the cork, passing throughout thereof. In this apparatus the bottle neck is insertable into a tubular housing in which a tubular shuttle is axially slidable and the shuttle includes a stop to limit the insertion depth of the bottle neck. The electric motor, with its rotation in a clockwise direction, firstly causes the bottle neck and the shuttle to be pulled towards the stop position within the tubular housing, while the corkscrew penetrates into the cork, and then, when the shuttle and bottle neck are stopped causes a further penetration of the corkscrew into the cork and the extraction of the cork from the bottle neck, due to the auger effect of the corkscrew. The cork is withdrawn almost completely from the bottle neck, until the cork strikes a sensor. By reversing the motor, the counterclockwise rotation of the corkscrew cause the push of the cork which does not rotate due to the presence of longitudinal ribs within the shuttle. This apparatus, even if allows to remove the cork almost completely from the bottle neck, has the drawback that the cork is always completed perforated by the corkscrew, so that little granulated parts of the same cork fall inside the bottle.
The present Applicant has devised and embodied this invention to overcome the shortcomings of the state of the art and to obtain further advantages.